Coupling structure to dynamics in crosslinked actin- microtubule composites*

Microtubules and actin are cytoskeletal filaments that shape the cell and play an important role in cell mobility and division. Both cytoskeletal filaments have distinct flexibilities and organizations in the cell that enable the production of work and resilience of the composite network. We seek to use such composite networks as a scaffold for smart materials with exciting properties such as self-healing and tunable stiffness. In order to use this network, we need to characterize the networks as a function of composition and crosslinking. We characterize the network structure visually using two color confocal microscopy to scan through the materials in 3D. We also measure the dynamics using the intensity fluctuations of the microtubules and the actin networks over time, the temporal autocorrelation, and fluorescence recovery after photobleaching. Networks with both malleability and elastic resilience will be useful as scaffolds for novel composite materials.